Shock-absorbing mechanism for vehicle-springs.



W. P. KIDDER.- V SHOCK ABSORBING MECHANISM FOR VEHIGLE SPRINGS.

'APPLIOATIONIILBD JAN.11,19 07.

' 1 Patented Feb. 2, 1909.

EE GE 5 UNITED ST-ATES PATENT OFFICE.

i r. itinbhit, OF BosTon, MAssAcHus 'rTs.

I sneca-assoasne mncziamsm r03 vnmctmsriiites.

Specification of Letters Patent.-

Patented Feb. 2, ieoe'.

Application filed Iaimary 11, 1907. Serial No. 361,744.

To all whom it may concern:

Be it known that I, WELLINGTON 1. Km-

DER, a citizen of the United States, residing in Boston, in the county of Suffolk and State of-Massachusetts, have invented a. new and useful Improvement in Shock-Absorbing Mechanism for Vehicle- Springs, 'of

' which the following is a specification.

My invention has for its object to provide a shockabsorbing mechanism particularly applicable to vehicle-springs, in which the depression and rebound ofthe vehicle-body are progressively checked by an increasing resistance as the spring is expanded and con tracted; in which such movements of the vehicle-body are positively limited at the end of the checking process without shock; in

which these results are produced with a minimum amount of interference with the freedom of normalspring action; and in which the emplo ment of lighter or softer springs is possib e with absolute protection fromdanger of breakage, such mechanism being adapted to be applied in connection and combination with springs of ordinary construction.

The nature of the invention is fully described below, and illustrated in the accompanying drawings, in which Figure 1 is a sectional side elevation showmg my lnventlon applied to the frame of a carriage-body, an a e and spring, with the spring in, its extreme contracted position,

and the frame supporting'the carriage-body I responding parts.

a represents a portion of the frame for supporting the body of a vehicle, and b is an ordinary carriage-spring, the one illustrated peing'of thesemi-elliptical type, connectdwith the body-frame by ordinary I mechanism 0 c.

d is the axle. d Rigidly seeu jed to the body-frame or to an part which is rigid with the body of the ve icle, is a vertically set cam e provided with a curved "or arc-sha edgroove e','s'aid' groove harm closed. en s inwhich are set stops g of leather or otherv suitable being (which is usually under the central portion 'of the sprin by means of 9. lug h is the lower end 0 a lever in whose upper endjis provided with a cam rollla whichextends into the cam-groove The pivot-pin n which extends. from the lower end of the lever is throu h the'lug his provided at its outer end witi a collar p, and between said collar and the stud with a s iral spring s. By this means a frictional rag-bearing is produced, the friction being applied 'between the flat contact surfaces of the lug h and'the lower end is of the lever is. This curved cam may be termed a double-acting wiper-cam, and when the spring is in its normal position the cam-roll is about onehalf' the distance up the cam. When a load is applied to the carriage-body the cam-roll moves from the central position in the cam up toward the upper. end, the resistance to. its movement g'ra ually increasing as it .ap-

material. Pivotally secured on the axle,-

proaches the upper stop g, such resistance multiplied by the frictional dragbearmg at the lower end of the lever. \Vhen the spring rebounds there is the same progressive frictional resistance as it moves from the position indicated in Fig. 2 to that indicated in Fig. -1. In each case there'is' a positive but gradualarrest of spring ac tion and the movement of the cam-roll is limited by the two sto s g and g which are in a vertical line so ocated as to prevent the lever from reaching a dead point.

Having thus fully described my invention, what I claim, and desire to secure by Letters Patent, is

1. In a shock-absorbing mechanism for vehicle-springs, a vehiclebody portion, a supporting axle, a spring intermediate of the axle and the body, a cam rigid with the bodyportion and provided with a curved camgroove, a lever pivotally connected with the axle and with its upper end in enga em'ent with the cam-groove, and a frictional drag mechanism bearing against said lever, for the purpose set forth.

2. In a shock-absorbing mechanism for vehicle-sprin s, a vehicle-body portion, a sup porting ax e, a s ring intermediate of the axle and the b0 y, a cam rigid with the body-portion" and provided with a curved cam-groove having'stops at its ends, a lever pivotally connected with the axle and with its upper end in engagement with the camgroove, and a frictional drag-mechanism bearing against said lever, for the purpose set forth.

3. In a shock-absorbing mechanism for vea ever pivot-' i i i l l i portion and provided with a curved camgroove, a lever pivotully connected with the axle and with its upper end in engagement with the cam-groove, stops supported by the body and adapted to prevent the lever from reaching a dead point, and a frictional drag mechanism bearing against said lever, for the purpose set forth,

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

WELLINGTON P. KIDDICR.

\Vitnesses 

